1. Field of the Invention
The present invention relates to apparatus for use in association with endoscopic medical video equipment. More particularly, this invention pertains to an improved endoscopic adapter.
2. Description of the Prior Art
The advent of various endoscopic instruments has proven to be a significant aid to both diagnosis and the performance of surgical procedures. This instrument comprises an elongated probe for penetration and viewing of otherwise-inaccessible body regions. Examples of endoscopic instruments include the laparascope, cystoscope, arthroscope, bronchoscope, colonoscope, etc. the functions and areas of use of which are apparent from the nomenclature.
The probe may be either flexible or rigid in accordance with its intended application. The physician is able to view the body region adjacent to the distal end of the probe through an eyepiece near the proximal end.
While providing a substantial technical advance, the utility of the endoscope has been significantly increased by the development of video cameras for coupling to the image output of the endoscope. The use of such a camera protects the vision of the physician in those instances in which a highly-reflective medium must be viewed with bright illumination. This often occurs in orthoscopic surgery where high intensity illumination of reflective bone tissue can cause injury to the retina of an operating physician.
The combination of video camera with the endoscope, as opposed to direct viewing, promotes the operator comfort and, hence, instrument utility. When using a camera, the physician needn't position himself throughout the examination to accommodate an eyepiece located near the proximal end of the endoscope. An assistant may hold and position the endoscope while the operating physician's hands are freed to manipulate the surgical tools. As the physician and his assistant may view the image at the same time on a common monitor, prompt and accurate movement of the scope is assured throughout the operation. Thus tissue trauma due to movements of the scope is lessened.
Finally, the incorporation of a video camera permits both recordation and real time transmission of procedures. This opens many possibilties not offered by conventional endoscopy including real time consultations (and teaching) from distant venues and significant documentation benefits.
The adaptation of video camera technology to endoscopic imaging requires a means for adapting the conventional endoscope to a video camera head. Conventional apparatus for this purpose include a mechanism for grasping the endoscope that is, in turn, coupled at its opposed end to the camera head. Viewing optics mounted within a sleeve are movable within an internal bore for focusing purposes. Means are provided in association with the adapter for focusing the optics.
A window is located the front or endoscope end of the adapter. Since the system is almost always employed within a critical environment, the entire system must be sterilized before use. This involves immersion of the equipment in a sterile bath for about fifteen minutes, followed by drying and assembly.
Viewing clarity is, of course, essential to the physician. This is often hampered during use by the presence of condensation on the front window of the adapter. This condensation results from the unavoidable presence of minute amounts of liquid on the surfaces of the adapter. Light energy that is coupled into the endoscope for illumination during operation heats the metallic portions of the instrument more than the glass window. As a result, some condensation generally takes place on the relatively cool front window which offers a lower moisture-pressure than the surrounding metal surfaces.
The resulting reduction in clarity can significantly hinder the physician's diagnostic ability. Alternatively, reduced clarity can limit the physician's ability to perform necessary procedures.